Rotary brush apparatuses are frequently used in vehicle wash systems for contacting, scrubbing, and cleaning exteriors of vehicles. These brushes typically include a rotary hub portion having an axis of rotation that is oriented generally parallel to a vehicle exterior and which includes a plurality of wash media elements that can extend outwardly from the hub portion. As the rotary hub rotates, the plurality of wash media elements extend generally outward due, in part, to centrifugal force, and can contact the vehicle exterior to remove dirt and debris and effectuate cleaning. To apply increased scrubbing and cleaning, the rotary hub can be rotated faster to increase the speed at which the media elements contact the vehicle exterior in order to generate more force to remove dirt. This generally creates an increased slapping noise due to the force of contact between the wash media elements and the vehicle and can make the car wash experience unenjoyable for a user. Also, as the speed of the brush increases, the perception of potential damage to the vehicle exterior increases.
Additionally, as most vehicle exteriors have non-planar or uneven surfaces, including on the lower or back part of the vehicle, the ability of these prior rotary brushes to adequately clean these surfaces can be limited. This is, in large part, because the wash media elements themselves are flexible and cannot apply sufficient force on the vehicle exterior to remove all dirt and debris. Accordingly, there remains a need for improvements in vehicle wash brush apparatuses to allow them to evenly scrub and clean such surfaces without the risk of scratching the vehicle exterior and which can accommodate non-planar surfaces.